JP2002079827A - Vehicular air-conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce fuel consumption of a vehicular engine by optimizing driving control of a cooling fan motor substantially continuously so as to suppress the total amount of consumed motive power small. SOLUTION: The vehicular air-conditioner comprises ambient air temperature recognizing means 15; vehicle speed recognizing means 14; controlled variable calculating means for calculating controlled variable of the cooling fan motor 12 by referring to a recognition value of each recognizing means; cooling fan motor driving control means for performing variable control depending on the calculated controlled variable; and consumed motive power calculating means for an air-conditioner apparatus for calculating the total consumed motive power W of the air-conditioner apparatus including the variable delivery compressor 5 and the cooling fan motor 12. The cooling fan motor controlled variable calculating means firstly calculates a target value Vp of the cooling fan motor voltage, and after operating such that the cooling fan motor voltage Vf approaches the target value Vp, the means repeatedly calculates and control the cooling fan motor voltage Vf to reduce the total consumed motive power W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner, and more particularly to a vehicle air conditioner having a cooling fan for an outdoor heat exchanger of a refrigeration circuit.

[0002]

2. Description of the Related Art A conventional vehicle air conditioner is shown in FIG.
The cooling fan is controlled as shown in FIG. In FIG. 7, an indoor heat exchanger, for example, an evaporator 10 is provided in an air-conditioning duct 101 leading to the vehicle interior.
2, an outdoor heat exchanger, for example, a condenser 103, is provided outside the air conditioning duct 101. Engine 104
, For example, a variable displacement compressor 1
The refrigeration circuit 107 is configured so that the refrigerant sent from the condenser 05 through the condenser 103 is expanded by the expansion valve 106 and supplied to the evaporator 102, and the refrigerant from the evaporator 102 is returned to the compressor 105. I have.

In the refrigeration circuit 107, the condenser 1
03 for generating a cooling airflow
And a motor 109 for driving the same.
When the refrigerant compressor 105 of the refrigeration cycle operates, the cooling fan motor 109 is on-off controlled in conjunction therewith. That is, the on / off control is performed via the cooling fan motor on / off control means 112 in conjunction with the compressor clutch control signal 111 from the main controller 110.

Alternatively, when the cooling fan motor 109 also serves as a cooling fan motor for a radiator in addition to the outdoor heat exchanger 103 of the refrigeration cycle, a signal from a vehicle speed sensor 113 and an engine cooling water temperature sensor are provided. The signal from the cooling fan motor 10
9 is applied with a predetermined voltage.

Accordingly, as shown in FIG. 8, the control is performed through the cooling fan motor on / off control means 112 in accordance with the compressor clutch signal Sm or the vehicle speed signal SP and the engine cooling water signal Tw in addition thereto. The fan motor 109 is controlled. In any case, the cooling fan motor 109 relies on simple on-off control, high-low two-stage voltage control, or at most high-low-off three-stage voltage control.

[0006]

However, in the control of the conventional cooling fan motor as described above, basically,
Only two-stage control of ON-OFF or high-low voltage is performed. To derive the control voltage of the cooling fan motor,
Since the total power consumption of the air conditioner is not considered, the cooling fan motor may not be operated in a state where the total power consumption is optimal. Accordingly, the operation of the cooling fan motor may increase the total power consumption of the air conditioner, thereby increasing the fuel consumption of the vehicle engine.

In addition, simply turning on / off or high voltage-
When only low two-stage control is performed, and the cooling control is not performed on the refrigeration cycle in consideration of the amount of heat released from the condenser (outdoor heat exchanger), thereby reducing the stability of the refrigeration cycle. There is. If the refrigeration cycle is unstable, the temperature of the air discharged from the duct will not be stable.

Further, since there are only two control states, ie, ON-OFF and voltage high-low, even when the heat radiation amount of the condenser is not much needed, the rotation speed of the cooling fan motor is higher than necessary. And may cause noise. Unnecessarily operating at a high rotation speed for an unnecessarily long time also causes a reduction in the life of the cooling fan motor.

Accordingly, an object of the present invention is to reduce the total power consumption of the entire air conditioner by optimizing the drive control of a cooling fan motor for an outdoor heat exchanger by focusing on the problems in the conventional control as described above. So that it can be suppressed,
Thereby, the fuel consumption of the vehicle engine is reduced.

Another object of the present invention is to improve the stability of the refrigeration cycle by optimizing the drive control of the cooling fan motor, thereby improving the stability of the temperature of the air blown from the duct, and to reduce the cooling fan motor. An object of the present invention is to increase the chances of operation at a rotational speed, extend the service life, and reduce noise.

[0011]

In order to solve the above problems, an air conditioner for a vehicle according to the present invention comprises an indoor heat exchanger provided inside an air conditioning duct and an outdoor heat exchanger provided outside the air conditioning duct. A refrigeration circuit including a variable displacement compressor driven by an engine, a cooling fan that generates a cooling airflow to the outdoor heat exchanger, and a vehicle air conditioner that includes a motor that drives the cooling fan. At least an outside air temperature recognizing means for detecting a temperature of the cooling air flow and a vehicle speed recognizing means for recognizing a traveling speed of the vehicle are provided, and a control amount of the cooling fan motor is calculated by referring to a recognition value of each recognizing means. A cooling fan motor control amount calculating means for performing the cooling fan motor drive control means for variably controlling a drive control amount of the cooling fan motor in accordance with the calculated control amount; An air conditioner device power consumption calculator for calculating a total power consumption W of the air conditioner device, including the compressor and the cooling fan motor, is provided. The cooling fan motor control amount calculating unit firstly outputs a target value of the cooling fan motor voltage. Vp is calculated and the cooling fan motor voltage Vf is set to the target value Vp
After that, the cooling fan motor voltage Vf is repeatedly calculated and controlled so that the total power consumption W decreases.

In the vehicle air conditioner, the cooling fan motor control amount calculating means may calculate the cooling fan motor voltage Vf with a certain voltage variation ΔV in a direction in which the total power consumption W decreases. The calculation and control are repeatedly performed in the direction of decreasing or increasing the fan motor voltage Vf, and when the total power consumption W starts to increase, the voltage change width ΔV is halved and the operation direction of the cooling fan motor voltage Vf is increased or decreased. It is preferable that the direction is reversed so that these series of operations and control are repeatedly performed.

Further, in the calculation of the cooling fan motor voltage Vf, the difference between the previous value and the current value of the variation width ΔV of the cooling fan motor voltage and / or the total power consumption W may be larger than a predetermined value. When it becomes smaller, or when a certain period of time has elapsed while the difference between the ΔV and / or the W is smaller than a predetermined value, each parameter value for deriving a target cooling fan motor voltage Vp formula stored in advance is used. Is updated, a new formula for calculating the target cooling fan motor voltage Vp is derived from the updated data by the least squares method, and the current calculation formula is newly calculated for the target cooling fan motor voltage Vp. Can be updated to the calculation formula.

Further, the cooling fan motor control amount calculating means calculates the target cooling fan motor voltage Vp by referring to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means in the calculation of the cooling fan motor voltage Vf. It is preferable to do so.

Further, in the calculation of the cooling fan motor voltage Vf, the cooling fan motor control amount calculating means repeats the target cooling fan motor voltage Vp by referring to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means. Preferably, when the difference ΔVp between the previous Vp and the current Vp has reached a predetermined value, the operation for calculating the cooling fan motor voltage Vf is preferably performed from the beginning based on the new Vp this time.

In the vehicle air conditioner according to the present invention as described above, when deriving the voltage of the cooling fan motor by calculation, the calculated value of the total power consumption W of each device for the air conditioner is considered. Is calculated as the optimum control voltage so that the total power consumption becomes smaller. Therefore, useless power consumption is suppressed, and the total power consumption of the entire air conditioner is reduced, so that the fuel consumption of the vehicle engine is also reduced.

Further, since the drive control of the cooling fan motor is steplessly optimized, the heat radiation state of the outdoor heat exchanger is steplessly optimally adjusted, whereby fluctuations in the state of the refrigerant in the refrigeration cycle are suppressed to a small level. Can be As a result, the fluctuation of the heat exchange performance in the indoor heat exchanger is suppressed to a small value, and the stability of the duct outlet air temperature is improved.

Furthermore, the stepless optimal control of the cooling fan motor increases the operating time at a low rotational speed compared with the conventional two-step control of on-off or high-low voltage, and the air conditioner described above. , While extending the life of the cooling fan motor and reducing noise.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a vehicle air conditioner according to one embodiment of the present invention. In FIG. 1, an evaporator 2 as an indoor heat exchanger is provided in an air conditioning duct 1, and a condenser 3 as an outdoor heat exchanger is provided outside the air conditioning duct 1. Vehicle engine 4
The refrigerant compressed by the variable capacity compressor 5 (variable capacity compressor) driven by the compressor is condensed in the condenser 3, sent to the evaporator 2 via the liquid receiver 6 and the expansion valve 7, and
The refrigeration circuit 8 is configured to return to the compressor 5 from the compressor. A displacement control signal is sent from the main controller 9 to the compressor 5, and a pressure detection signal is sent from a high pressure sensor 10 provided on the high pressure side of the refrigeration circuit 8 to the compressor 5.
Sent to

The condenser 3 of the refrigeration circuit 8 is provided with a cooling fan 11 for generating a cooling air flow.
The cooling fan 11 is driven by a cooling fan motor 12. The driving of the cooling fan motor 12 is controlled through a cooling fan voltage controller 13 as a cooling fan motor drive control unit based on a cooling fan motor control amount signal from a main controller 9 as a cooling fan motor control amount calculation unit. You. The main controller 9 includes a vehicle speed signal from a vehicle speed sensor 14 as a vehicle speed recognition unit, an outside air temperature signal from an outside air temperature sensor 15 as an outside air temperature recognition unit, and a cooling water temperature to calculate the cooling fan motor control amount. A cooling water temperature signal from an engine cooling water temperature sensor 16 as recognition means, a vehicle interior temperature signal from a vehicle interior temperature sensor 17 as vehicle interior temperature recognition means,
A signal from an evaporator outlet air temperature sensor 18 provided on the downstream side of the evaporator 2 is input.

At the inlet side of the air conditioning duct 1, an outside air inlet 2
1 and a switching damper 23 for switching the amount of intake air between an inside air inlet 22 and an intake actuator 2 for adjusting the same.
4 are provided. Further, a fan voltage controller 27 for controlling the voltage of the fan 25 of the blower and its motor 26 is provided. In the present embodiment, on the downstream side of the evaporator 2, a hot water heater 2 through which engine cooling water flows is provided.
8 is provided, and an air mix damper 29 is provided immediately downstream thereof. The opening degree of the air mix damper 29 is determined based on a signal from the main controller 9.
It is controlled via the air mix damper actuator 30.

Reference numerals 31, 32, and 33 denote temperature-controlled air outlets into the passenger compartment, respectively, and each of the outlets is provided with dampers 34, 35, and 36 for adjusting the opening. In this embodiment, the electric outlet 37 is provided with the electric heater 37, and the voltage of the electric heater 37 is controlled via the electric heater voltage controller 38 based on a signal from the main controller 9.

In the main controller 9, calculation of the cooling fan motor control amount is performed, for example, as shown in FIGS. The flowcharts shown in FIGS. 2 and 3 show a main routine, and first enter a subroutine in step S1. In the subroutine, as shown in FIG. 4, the outside air temperature Tout and the vehicle speed SP are input (step S101,
S102), the target cooling fan motor voltage Vp is calculated by Vp = f (Tout, SP) (step S103). First, the initial value V0 of the target cooling fan motor voltage is input, and the difference between the target cooling fan motor voltage Vp (current value) and the previous value, the target cooling fan motor voltage Vp ', is calculated (steps S104 and S105). ).

Returning to the main routine shown in FIG. 2, the cooling fan motor control voltage change width ΔVa obtained by halving the target cooling fan motor voltage ΔVp is added to the previous cooling fan motor control voltage Vf ′, and a new cooling fan motor control is performed. After operating as the voltage Vf, the total power consumption W0 of the air conditioner is calculated.
Is calculated (steps S2 to S5).

Subsequently, the cooling fan motor control voltage change width Δ
Va is set to the previous cooling fan motor control voltage Vf ′ (step S
4 and Vf) is operated as a new cooling fan motor control voltage Vf, and the total power consumption W1 of the air conditioner is calculated (steps S6 to S8). Subsequently, the subroutine of FIG. 4 is executed (step S9), and it is determined whether or not the target cooling fan motor voltage change amount ΔVp is within a range of ± A (predetermined value) (step S10). For example, the total power consumption W0 and W1 of the air conditioner is compared (step S11). Comparing the total power consumption W0 and W1 of the air conditioner, when W1 is large, as shown in FIG. 3, the cooling fan motor control voltage change width ΔVb is reduced by half to the previous cooling fan motor control voltage Vf. ', And operated as a new fan control voltage Vf, to calculate the total power consumption W2 of the air conditioner (step S12).
To S15). Subsequently, the subroutine of FIG. 4 is executed (step S16), and the target cooling fan motor voltage variation Δ
If Vp is within the range of ± A, the total power consumption W1 and W2 of the air conditioner is compared (steps S17 and S18). Comparing the total power consumption W1 and W2 of the air conditioner, W2 is large and the cooling fan motor control voltage change width ΔVb is within a range of ± B (predetermined value), and the absolute value of the difference between W1 and W2 is C If smaller, the current outside air temperature Tout, vehicle speed SP, and cooling fan motor control voltage Vf are stored in the memory (steps S19 and S20).

From the stored information, by the least squares approximation method,
The target cooling fan motor voltage Vp formula is derived (step S
21), after updating the current Vp expression (the Vp expression in FIG. 4) to a new Vp expression (step S22), ST in the flowchart.
Return to ART.

If the target cooling fan motor voltage change amount ΔVp is not within the range of ± A in step S10, the process returns to step S2. In step S11, W0
If not <W1, the process returns to step S6. When ΔVp is not within the range of ± A in step S17, the process returns to step S2, and in step S18, W1 <W2
If not, the process returns to step S13. Further, when step S19 is not established, the step S1 is repeated.
Return to 2.

In the above flowchart, the total power consumption W is calculated, for example, as shown in FIG. Also,
Target cooling fan motor voltage Vp in flowchart
Is derived, for example, as shown in FIG.

In the example shown in FIG. 5, as the detected amounts, the evaporator outflow air temperature Teout, the outside air temperature Tout, the inside air temperature Tin, the intake state INT, and the blower voltage calculation value BL
V, compressor capacity control signal Ic, high pressure Pd, cooling fan motor voltage Vfan, battery voltage VB, and electric heater voltage Vh. The evaporator inflow air temperature Tein is calculated by Tein = Tout × α + Tin × (1−α), and the refrigerant flow rate Gr is calculated by Gr = f (Qe, ΔIe). Here, Qe = f (Tein, BLV, Teout) ΔIe = f (Ps, Pd) Ps = f (Ic). Here, Qe: cooling capacity ΔIe: evaporator enthalpy difference Ps: compressor suction pressure

Then, the compressor power consumption Wcmp is calculated by Wcmp = f (Gr, Ps, Pd), where Ps = f (Ic).

In addition, the power consumption We of the air conditioner other than the compressor.
lc is expressed as Welc = η × f (Wfan, Wcl, Wblv, W
h) Obtain with. Where Wfan = f (Vfan) Wcl = f (VB) Wblv = f (BLV) Wh = f (Vh) η: Alternator efficiency.

The sum W of the compressor power consumption Wcmp and the other power consumption Welc is obtained as W = Wcmp + Welc.

FIG. 6 shows the concept of obtaining the arithmetic expression for the target cooling fan motor voltage Vp in the subroutine of FIG. 4 described above.

As shown in FIG. 6, the total power consumption of the air conditioner is the sum of the power consumption Wcomp of the compressor and the power consumption Welc of various electric devices, and the power consumption of various electric devices includes the power generated by the prime mover (engine). On the other hand, the power is added to the efficiency of the alternator / regulator. The compressor consumption power Wcomp is calculated based on various conditions (evaporator outflow air temperature Teout, outside air temperature Tout, inside air temperature Tout).
in, intake state INT, blower voltage calculation value BL
V, compressor capacity control signal Ic, high pressure P of the refrigeration circuit
d), and the power consumption Welc of the electric equipment also depends on various conditions (cooling fan motor operating voltage V
fan, the battery voltage VB, the electric heater voltage Vh, and the blower voltage calculation value BLV).

The correlation (correlation data) between the total power consumption W of the air conditioner, which is the sum of these power consumptions, and the cooling fan motor voltage Vfan (ie, the actual drive control amount of the cooling fan motor) is represented by each parameter. (Each explanatory variable) is taken for each. In other words, Vfan is set as the target variable, that is, the target cooling fan motor voltage Vp, and each parameter is set as an explanatory variable, and a correlation is obtained for each of the explanatory variables. Then, the outside air temperature Tout and the vehicle speed SP are used as explanatory variables, and the cooling fan motor voltage Vp is used as an objective variable.
A correlation is required. The correlation between Vfan (Vp) and W is generally data having the lowest extreme value (minimum value) as shown in the figure for each explanatory variable. Vfan (Vp) which is the minimum value Wmin or W in the vicinity thereof
, The power consumption of the cooling fan motor can be optimally reduced according to the conditions at that time. In the simple on / off control of the cooling fan motor voltage and the two-level control of the cooling fan motor, it is not possible to reduce the power consumption of the cooling fan motor and optimize the cooling fan motor voltage control according to the conditions at that time.

Based on such a technical idea, a correlation equation f between the objective variable and the explanatory variable is derived from the correlation data. A correlation equation of Vp = f (Tout, SP) is derived, and using this correlation equation, a calculation is performed as shown in the above-described subroutine of FIG. 4, and according to the condition at that time, the cooling fan motor voltage is actually calculated. Controller 13
The command signal to be output to is determined.

In such control, the voltage of the cooling fan motor can be optimally controlled substantially steplessly according to the state of the vehicle and the air conditioner at that time. In other words, the cooling fan motor voltage is controlled so that the total power consumption of the air conditioner is reduced as much as possible, and at the same time, is controlled so that the fluctuation of the refrigerant state of the refrigeration cycle is suppressed and the duct outlet air temperature fluctuation is suppressed. . Since the total power consumption of the air conditioner is kept low, the fuel consumption of the vehicle engine is kept low, and the stability of the refrigeration cycle ensures the stability of the duct outlet air temperature.

Further, since the chance of operating the cooling fan motor at a low rotation speed increases, the life of the cooling fan and the motor can be extended and the noise can be reduced.

[0039]

As described above, according to the vehicle air conditioner according to the present invention, the total power consumed by the air conditioner is taken into consideration, and the power to be used for the cooling fan is optimized according to the state at that time. , The power consumption of the cooling fan, and thus the total power consumption of the air conditioner, can be reduced, and the fuel consumption of the vehicle engine can be reduced.

Further, since the cooling fan can be optimally controlled substantially steplessly, the stability of the temperature of the air blown out from the duct can be improved, and the cooling fan can be operated at a low rotation speed. It is also possible to reduce noise.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a vehicle air conditioner according to an embodiment of the present invention.

FIG. 2 is a flowchart showing control of the apparatus of FIG.

FIG. 3 is a flowchart showing a continuation of the flow of FIG. 2;

FIG. 4 is a flowchart showing a subroutine in the flow of FIG. 2;

FIG. 5 is a block diagram illustrating an example of a calculation of total power consumption in the flow of FIG. 2;

FIG. 6 is an explanatory diagram showing an example of deriving a target cooling fan motor voltage calculation expression in the subroutine of FIG. 4;

FIG. 7 is a schematic configuration diagram of a conventional vehicle air conditioner.

FIG. 8 is a block diagram showing control of the device of FIG. 7;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 air conditioning duct 2 evaporator as indoor heat exchanger 3 condenser as outdoor heat exchanger 4 vehicle engine 5 variable capacity compressor 6 liquid receiver 7 expansion valve 8 refrigeration circuit 11 cooling fan 12 cooling fan motor 13 cooling fan Voltage controller 14 Vehicle speed sensor 15 Outside air temperature sensor 16 Engine cooling water temperature sensor 17 Car interior temperature sensor 18 Evaporator outlet air temperature sensor 21 Outside air inlet 22 Inside air inlet 23 Switching damper 24 Intake actuator 25 Blower fan 26 Blower motor 27 Blower voltage Controller 28 Hot water heater 29 Air mix damper 30 Air mix damper actuator 31, 32, 33 Air outlet 34, 35, 36 Damper 37 Electric heater 38 Electric heater voltage controller

Claims (5)

[Claims] 1. A refrigeration circuit including an indoor heat exchanger provided in an air conditioning duct, an outdoor heat exchanger provided outside the air conditioning duct, a variable displacement compressor driven by an engine, and the outdoor heat exchange. A vehicle air conditioner having a cooling fan for generating a cooling airflow to a cooling device and a motor for driving the cooling fan, at least an outside air temperature recognition means for detecting a temperature of the cooling airflow, and a traveling vehicle speed of the vehicle. And a cooling fan motor control amount calculating unit that calculates a control amount of the cooling fan motor with reference to the recognition value of each recognition unit, and a cooling fan motor control unit that calculates the control amount of the cooling fan motor according to the calculated control amount. Cooling fan motor drive control means for variably controlling the drive control amount is provided, and the total power consumption W of the air conditioner equipment including the compressor and the cooling fan motor is repeated. The cooling fan motor control amount calculation means first calculates a target value Vp of the cooling fan motor voltage and calculates the cooling fan motor voltage Vf so as to approach the target value Vp. After the operation, the air conditioner for a vehicle is characterized by repeatedly calculating and controlling the cooling fan motor voltage Vf so that the total power consumption W decreases. 2. The cooling fan motor control amount calculating means decreases or increases the cooling fan motor voltage Vf by a certain voltage change width ΔV in a direction in which the total consumed power W decreases in the calculation of the cooling fan motor voltage Vf. When the total power consumption W starts to increase, the voltage change width ΔV is halved, and the operation direction of the cooling fan motor voltage Vf is reversed to increase or decrease. The vehicle air conditioner according to claim 1, wherein the calculation and the control of are repeatedly performed. 3. The cooling fan motor control amount calculating means, in the calculation of the cooling fan motor voltage Vf, the difference between the previous value and the current value of the variation width ΔV of the cooling fan motor voltage and / or the total power consumption W is larger than a predetermined value. When it becomes smaller, or when a certain period of time has elapsed while the difference between the ΔV and / or the W is smaller than a predetermined value, each parameter value for deriving a target cooling fan motor voltage Vp formula stored in advance is used. Is updated, a new formula for calculating the target cooling fan motor voltage Vp is derived from the updated data by the least squares method, and the current calculation formula is newly calculated for the target cooling fan motor voltage Vp. The vehicle air conditioner according to claim 1, wherein the vehicle air conditioner is updated to a calculation formula. 4. The cooling fan motor control amount calculation means calculates a target cooling fan motor voltage Vp with reference to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means in the calculation of the cooling fan motor voltage Vf. , Claim 1
4. The vehicle air conditioner according to any one of claims 1 to 3. 5. The cooling fan motor control amount calculating means repeatedly calculates a target cooling fan motor voltage Vp with reference to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means in the calculation of the cooling fan motor voltage Vf. When the difference ΔVp between the previous Vp and the current Vp has reached a predetermined value, the operation of calculating the cooling fan motor voltage Vf is changed to the new Vp
The air conditioner for a vehicle according to claim 4, wherein the air conditioning is performed from the beginning based on the following.